pdl> $frame = zeroes 19,19 pdl> ($x,$y,$r,$xmax,$ymax) = (5,4,6,dims $frame) pdl> pdl> use List::Util pdl> *min_ = \*List::Util::min pdl> *max_ = \*List::Util::max pdl> pdl> ($llx,$lly,$urx,$ury,$cx,$cy) = ( > max_(0,$x-$r), > max_(0,$y-$r), > min_($xmax,$x+$r), > min_($ymax,$y+$r), > min_($r,$x), > min_($r,$y)) pdl> pdl> $viewport = $frame($llx:$urx, $lly:$ury) pdl> pdl> $viewport .= $viewport-> rvals({ > Center => [$cx,$cy], > Squared => 1 > }) <= $r*$r pdl> pdl> p $frame [ [0 1 1 1 1 1 1 1 1 1 0 0 0 0 0 0 0 0 0] [1 1 1 1 1 1 1 1 1 1 1 0 0 0 0 0 0 0 0] [1 1 1 1 1 1 1 1 1 1 1 0 0 0 0 0 0 0 0] [1 1 1 1 1 1 1 1 1 1 1 0 0 0 0 0 0 0 0] [1 1 1 1 1 1 1 1 1 1 1 1 0 0 0 0 0 0 0] [1 1 1 1 1 1 1 1 1 1 1 0 0 0 0 0 0 0 0] [1 1 1 1 1 1 1 1 1 1 1 0 0 0 0 0 0 0 0] [1 1 1 1 1 1 1 1 1 1 1 0 0 0 0 0 0 0 0] [0 1 1 1 1 1 1 1 1 1 0 0 0 0 0 0 0 0 0] [0 0 1 1 1 1 1 1 1 0 0 0 0 0 0 0 0 0 0] [0 0 0 0 0 1 0 0 0 0 0 0 0 0 0 0 0 0 0] [0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0] [0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0] [0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0] [0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0] [0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0] [0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0] [0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0] [0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0] ] pdl>